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81.
Hepatitis B surface antigen (HBsAg) has been reported to be present in other organs than the liver.3,9 So far as our knowledge is concerned, however, any report of cases dealing with pancreatic diseases induced by hepatitis B virus (HBV) has not been described in the English and Japanese literature. We report an autopsy case with a pancreatic lesion characterized by damage of both exocrine and endocrine epithelial cells with inflammatory response, which were immunohistochemically found to be positive for HBsAg, and electron-microscopically to possess core-like particles In the nucleus and cytoplasm.  相似文献   
82.
The sinusoidal structure and blood supply of 38 liver nodules less than 2 cm In diameter were Investigated. There were 18 cases of adenomatous hyperplasia (AH) and 20 cases of hepatocetlular carcinoma (HCC). Growth pattern, encapsulation and vascularity were examined, and Immunohistochemistry performed for factor VIII related antigen (factor VIII), type IV collagen (collagen IV), lamlnln and CD68. There were significant differences between AH and small HCC, except for the expression of CD68. There were differences In tumor size, vasculartty and the components of the basement membrane between AH and small, well differentiated HCC. The cases of AH were supplied by the portal system and maintained the sinusoidal structure, but small well-differentiated HCC were supplied by a mixture of portal and arterial vessels. In spite of their small size, moderately and poorly differentiated HCC had capillary and were supplied by branches of the hepatic artery.  相似文献   
83.
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.  相似文献   
84.
We examined the major pathogenic substances of Bordetella pertussis for the ability to induce nitric oxide, and important biological function of macrophages, via gamma interferon in spleen cells. B. pertussis, which produces a variety of pathogenic substances, including pertussis toxin and filamentous hemagglutinin, causes a severe respiratory disease. Nitric oxide was detected in the culture fluid of spleen cells stimulated with pertussis toxin or its B oligomer but not in the culture fluid of spleen cells stimulated with the A protomer of pertussis toxin or with filamentous hemagglutinin. Incubation of the peritoneal exudate macrophages with pertussis toxin, B oligomer, A protomer, or filamentous hemagglutinin induced little nitric oxide, whereas incubation with gamma interferon induced a significant amount of nitric oxide. The induction of nitric oxide in spleen cells stimulated with pertussis toxin was completely inhibited by anti-gamma interferon antibody. The treatment of spleen cells with anti-Thy-1.2 antibody plus complement followed by stimulation with pertussis toxin decreased the secretion of gamma interferon and nitric oxide. These results suggest that gamma interferon from T lymphocytes stimulated with pertussis toxin induces nitric oxide.  相似文献   
85.
Mitochondrial DNA (mtDNA) is inherited maternally in most eukaryotes. Linear mitochondrial plasmids in higher plants and fungi are also transmitted from the maternal parent to the progeny. However, mF, which is a mitochondrial linear plasmid of Physarum polycephalum, evades uniparental mitochondrial inheritance. We examined 36 myxamoebal strains of Physarum and isolated three novel mF+ strains (JE8, TU111, NG111) that harbored free mF plasmids. These strains were mated with the mF strain KM88. Of the three mF × mF+ crosses, only KM88 × JE8 displayed complete uniparental inheritance. However, in KM88 × TU111 and KM88 × NG111, the mtDNA of KM88 and mF of TU111 and NG111 were inherited by the plasmodia and showed recombination. For example, although the mtDNA of TU111 was eliminated, the mF of TU111 persisted and became inserted into the mtDNA of KM88, such that recombinant mtDNA represented 80% of the total mtDNA. The parental mitochondria fused to yield giant mitochondria with two or more mitochondrial nucleoids. The mF appears to exchange mitochondria from the recipient (paternal) to the donor (maternal) by promoting mitochondrial fusion.The first two authors have equally contributed to this work  相似文献   
86.
Novel segmented multiblock copolymers ( 7 ) were synthesized by linking poly(ethylene oxide) (PEO) blocks with poly(β-benzyl L -aspartate)(PBLA) blocks via urethane and urea bonds, which were formed by the reaction of 4,4′-methylenediphenyl isocyanate ( 5 ) with the terminal hydroxyl groups of α-hydro-ω-hydroxypoly(oxyethylene) ( 4 ) and the terminal amino groups of poly(β-benzyl L -aspartate)-block-iminohexamethyleneimino-block-poly(β-benzyl L -aspartate) ( 3 ) [prepared from 1,6-hexanediamine ( 1 ) and β-benzyl L -aspartate N-carboxy anhydride ( 2 )], respectively. Membranes with various water contents were obtained from these copolymers by changing the lengths of the PEO and PBLA segments. The study of the permeation of 1-phenyl-1,2-ethanediol, vitamin B12 and myoglobin through the membranes showed a high dependency of the permeability on the molecular weight of the solutes.  相似文献   
87.
A thermostable direct hemolysin was purified from culture filtrates of Vibrio parahaemolyticus. The purified hemolysin gave one precipitation line with the antihemolysin antiserum on agar-gel diffusion test and a single band on polyacrylamide gel electrophoresis. The hemolysin was not inactivated by heating at 70 to 100 C for 10 min. The hemolytic activity was not enhanced by the addition of lecithin. It was demonstrated that the hemolysin was a protein with a molecular weight of approximately 118,000. Amino acid analysis revealed that 43% of total amino acids were acidic amino acids, whereas 11% were basic amino acids.  相似文献   
88.
89.
A rare case Is descrlbed of an Intramural sarcoma of the rlght common carotld artery coexistlng wlth adventitial inflammation and flbrosls, resembllng 'inflammatory aneurysm', which was resected from a 33-yearold Japanese woman who had presented with a pulsatile mass on the rlght side of the anterior neck. Grossly, the wall of the carotld artery showed an intimal tear with dlssectlon of the medla filled with thrombus. A graylsh area, abutting directly onto the dlssected space and Involving the media and inner adventltia, was composed of a-smooth muscle actin-positive and desmln-negative polygonal and splndle cells with large bluntended nuclei and coarse granular chromatin arranged Into a well-organized Interlacing bundle pattern. This portlon was thus considered to represent lelomyosarcoma. White to yellow-tan fibrotic tissue present in the adventitial area consisted of extensive lamellar fibrosis wlth scattered focl of lymphoplasmacytlc aggregates and obliterated arteries, and lacked atypical spindle and polygonal cells. These changes accorded with the histopathologlcal findlngs hitherto described in cases of 'inflammatory aneurysm', which is known to almost exclusively involve the abdominal aorta. We conslder this case unique In that the leiomyosarcoma involved an artery other than the aorta, wlth an 'inflammatory aneurysm'-like reaction in the same she. The posslble relatlonship between these two condltions Is dlscussed.  相似文献   
90.
Adenosine has dose-dependent biphasic excitatory and inhibitory effects on neurotransmission in the hippocampus. The mechanism of the excitatory action is not known although that of the inhibitory action has been well analyzed. Here we report on the mechanism of excitatory action of adenosine, using hippocampal slices. Studies of intracellular recordings of CA3 pyramidal neurons showed that the amplitude of EPSP was dramatically enhanced by application of adenosine at low concentration (0.1 microM) without changing resting membrane potentials, membrane conductance or the threshold for spike generation by injecting current pulses. On the other hand, the presence of adenosine at a concentration of 0.1 microM during electrical stimulation to the slices increased 1.7 times the release of glutamate, an excitatory neurotransmitter in the hippocampus. These results indicate that the excitatory action of adenosine at low doses is due to the increase of transmitter release.  相似文献   
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